Theme for custom UIActivity

Question

How to indicate that a user UIActivitysupports a theme?

The documentation for the UIActivityItemSource protocol mentions that you can implement an additional selector activityViewController:subjectForActivityType:if you want the source to provide a Header:

When sending goods, the service can provide a separate subject field and data field, for example, an e-mail message. Add this method if you want to provide a subject field for services that support it.

But as far as I can tell, it is not documented anywhere, how can I actually indicate that my custom UIActivity supports the theme. How it's done?

Edit: To make my question clearer

Suppose I have a custom action item object, say DocumentActivityItemSourcethat implements the protocol UIActivityItemSource, and I have a custom UIActivityone that we can name SendWithFooMessageActivity.

Then I run the UIActivtyViewController:

NSArray *activityItems = @[[[DocumentActivityItemSource alloc] initWithDocument: document]];
NSArray *applicationActivities = @[[[SendWithFooMessageActivity alloc] init]];
UIActivityViewController *activityViewController = [[UIActivityViewController alloc] initWithActivityItems:activityItems
                                                                                     applicationActivities:applicationActivities];
[parentViewController presentViewController:activityViewController
                                   animated:YES
                                 completion:nil];

Now in the pop-up window, select SendWithFooMessageActivity. Then, the activity controller will call activityViewController:itemForActivityType:on the instance DocumentActivityItemSourceto get the item, which will then be redirected to SendWithFooMessageActivityby calling this method prepareWithActivityItems:.

A normal activity element will be an image, line, or URL. In this case, let's say that it DocumentActivityItemSourcereturns a line with an outgoing advertising message about the document. It SendWithFooMessageActivitycan then use this text as the body of this foo-mail message.

Foo , . , UIActivityItemSource activityViewController:subjectForActivityType:, , .

Apple, , - activityViewController:subjectForActivityType: DocumentActivityItemSource, .

, , , SendWithFooMessageActivity ActivityCem? , ", []", - , .

, activityViewController:thumbnailImageForActivityType:suggestedSize:, ", ". ShareOnTwitter ShareOnFacebook , , , , . ?

, @chriszumberge, ActivityViewController , items:

[SendWithFooMessageActivity alloc] initWithSubject: document.title];

, UIActivityViewController.

Answer 1

:

UIActivityViewController *activityVC = [[UIActivityViewController alloc] 
    initWithActivityItems:@[@"Info you're emailing out."] applicationActivities:nil];
[activityVC setValue:@"Custom Email Subject Here" forKey:@"subject"];

, UIActivity , , , , MFMailComposeViewController .

UIActivityItemProvider , - UIActivity UIActivityViewController. ,

- (id)activityViewController:(UIActivityViewController *)activityViewController itemForActivityType:(NSString *)activityType

.

UIActivity - (UIViewController*) activityViewController, .

MFMailComposeViewController *mailCVC = [[MFMailComposeViewController alloc] init];
mailCVC.mailComposeDelegate = self;
[mailCVC setSubject:theSubject];
[mailCVC setMessageBody:theMessage isHTML:NO];
[mailCVC addAttachmentData:theData mimeType:@"text/csv" fileName:theFileName];

UIActivityItemProvder , UIActivityViewController , ( Apple). activityViewController:subjectForActivityType: UIActivityItemSource.

UIActivityItemProvider UIActivityItemSource. , subjectForActivityType:.

switch/case if, , [activityType isEqualToString:@"Custom UIActivity Title"] UIActivity activityTitle. , , . UIActivityItemProvider.

Answer 2

, .

, . activityViewController, -(void)performActivity.

, :

NSString *subject = nil;
if ([item respondsToSelector:@selector(activityViewController:subjectForActivityType:)]
{
     subject = [item activityViewController:activityViewController subjectForActivityType:activityType];
}